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chmod calculator
Tick permissions or type a mode like 755 or rwxr-xr-x to get the chmod command.
| Read | Write | Execute | Special | |
|---|---|---|---|---|
| Owner | ||||
| Group | ||||
| Others |
Octal Symbolic
Command
Common questions
What do the numbers in chmod 755 mean?
Each digit is one group of users: owner, group, then others. Add 4 for read, 2 for write and 1 for execute. So 7 is read, write and execute, and 5 is read and execute.
What does the fourth digit do?
A leading digit sets special bits: 4 is setuid, 2 is setgid and 1 is sticky. 1777 is the mode of /tmp: everyone can write, but only the owner can delete their own files.
What permissions should an SSH key have?
Private keys should be 600 (or 400) and the ~/.ssh folder 700. SSH refuses keys that other users can read.
Why does ls show a capital S or T?
A capital S or T means the special bit is set but the execute bit underneath it is not, which is usually a mistake.
Is my input sent anywhere?
No. Everything runs in your browser.